Yarn cutting device

ABSTRACT

A cutting device for cutting-off tufts of yarn for use with a tufting machine comprising a body having a portion defining a cutter-shaft contacting surface defining at least one yarn entry passage and at least one air passage communicating, a cutter shaft slidably displaceable over said surface and having wall portions defining at least one tuft displacing passage extending therethrough, ducting means aligned with the displacing passage of said shaft to receive tufts therefrom when the shaft is displaced to be in communication with said air passage, and yarn feed means adapted to feed yarn through said yarn entry passage into the tuft displacing passage of the shaft when aligned therewith; said tuft displacing passage and cutter shaft being displaceable from alignment with the yarn entry passage into alignment with said air passage and co-operate with said yarn entry passage and cutter-shaft contacting surface to sever yarn when supplied by said feed means.

United States Patent 1 Hasler ct al.

[4 1 Apr. 2, 1974 YARN CUTTING DEVICE Taylor, 34 Hertford St., MillHill, both of Blackburn, England [22] Filed: Mar. 23, 1972 [21] Appl.No.: 237,309

[30] Foreign Application Priority Data Mar. 23, 1971 Great Britain7626/71 [52] U.S. Cl 83/98, 83/200, 83/277, 83/282, 83/913 [51] Int. ClD01g 1/04, B65h 51/16 [58] Field of Search 83/98, 99, 199, 200, 580,83/277, 282, 913

[56] References Cited UNITED STATES PATENTS 1,336,605 4/1920 Becker83/199 X 3,031,003 4/1962 Clemons 83/199 X FOREIGN PATENTS ORAPPLICATIONS 172,595 7/1965 U.S.S.R 83/199 Primary ExaminerFrank T. YostAttorney, Agent, or Firm-Sughrue, Rothwell, Mion, Zinn & Macpeak [57]ABSTRACT A cutting device for cutting-off tufts of yarn for use with atufting machine comprising a body having a portion defining acutter-shaft contacting surface defining at least one yarn entry passageand at least one air passage communicating, a cutter shaft slidablydisplaceable over said surface and having wall portions defining atleast one tuft displacing passage extending therethrough, ducting meansaligned with the displacing passage of said shaft to receive tuftstherefrom when the shaft is displaced to be in communication with saidair passage, and yarn feed means adapted to feed yarn through said yarnentry passage into the tuft displacing passage of the shaft when alignedtherewith; said tuft displacing passage and cutter shaft beingdisplaceable from alignment with the yarn entry passage into alignmentwith said air passage and co-operate with said yarn entry passage andcutter-shaft contacting surface to sever yarn when supplied by said feedmeans.

7 Claims, 2 Drawing Figures SHEET 1 (IF 2 PATENTED APR 2 I974 YARNCUTTING DEVICE Prior application: In Great Britain on March 23, 1971 andnumbered 7626/71.

The present invention relates to a cutting device for cuttingoff shortlengths of yarn from a supply thereof, and is particularly suitable foruse with a tufting machine in which the cutting device is required tocut-off such lengths of yarn from one or more yarn supplies and feedthem to a hollow needle of the tufting machine.

A tufting machine for manufacturing a tufted carpet in which the cuttingdevice may be used is one in which a plurality of hollow needles extendalong a needle bar which is reciprocated so that the needles passthrough and are retracted from a backing fabric. A short length or tuftof yarn is passed through the passage formed in each of the hollowneedles and is inserted in the backing fabric and may have an adhesiveor other means supplied thereto to ensure retention in the backing. Sucha tufting machine requires a device for cutting desired lengths of yarnand enabling them to be fed to the needle bar.

According to the present invention there is provided a cutting devicefor cutting-off short lengths or tufts of yarns from a yarn supply,comprising a body having a portion defining a cutter-shaft contactingsurface and having at least one yarn entry passage and at least one airpassage communicating with said surface, a cutter shaft slidablydisplaceable over said surface and having at least one tuft displacingpassage extending therethrough, ducting means aligned with thedisplacing passage of said shaft to receive tufts therefrom when theshaft is displaced to be in communication with said air passage, andyarn feed means for feeding yarn through said yarn entry passage intothe tuft displacing passage of the shaft when aligned therewith; thetuft displacing passage and cutter shaft being displaceable fromalignment with the yarn entry passage into alignment with the airpassage and co-operate with the yarn entry passage and cutter-shaftcontacting surface to sever yarn when supplied by the feed means. Thebody of the cutting device will preferably define a channel portionwhich will provide the cutter-shaft contacting surface, and the cuttershaft will have a co-operating surface corresponding therewith.

Preferably the cutter shaft will be in the formof a cylindrical bar andthe channel be of corresponding partcircular section. In this preferredarrangement, the cutter shaft may be displaceable to execute circularrotation or oscillatory movement which may be axial or rotary and inwhich latter case, the amplitude will preferably be substantially 22% or90.

Preferably a plurality of yarn entry passages will be provided in thebody and supplied by a plurality of yarn feed means. A correspondingplurality of air passages and tuft displacing passages will be providedand the passages in each group may be arranged in straight lineformation or relatively offset about a line to reduce the overalldimensions of the device. A plurality of tuft ducting means will also beprovided and, in use, each be communicatable with a needle of a tuftingmachine.

The body may be a composite one made up of a number of connectedsections. When the cutter shaft is in the form of a cylindrical bar, itmay be provided on the side away from the yarn entry passage with springloaded or other clamping means which urge the operative portion of theshaft against the operative contacting surface of the body thus ensuringthat the cutter shaft surface and the contacting surface of the body arein close contact and there fore capable of making a clean and sharp cutthrough the yarn. The ducting means may comprise a flexible tube,preferably of plastics material, connected to the outlet orifice of eachtuft displacing passage in the cutter shaft when such is arranged toexecute oscillatory movement or may comprise an aperture extendingthrough a body section of the device. In either event, the ductingmeans, in use, communicates with or is located in the main tuft feedline of a tufting machine. Each needle of such a machine maybeassociated with a plurality of cutters.

The cutting device will include a yarn feed means which operated todisplace predeterminable lengths of yarn through the yarn entry passageinto the displacing passage of the cutter shaft. The yarn feed means maycomprise a member having a channel along which yarnmay pass, anintermittently driven wheel having a portion extending into or adjacenta first opening communicating with the channel and a displaceablepressure means, for example, a roller or skid, substantially op- .positesaid wheel portion and displaceable through a second openingcommunicating with the channel to urge yarn against said wheel to feedthe yarn through the channel means and yarn entry passage communicatingtherewith into the passage in the cutter shaft. The pressure means maybe carried by a piston rod and piston and cylinder arrangement and bespring biassed away from the yarn. The piston may be pneumaticallydisplaceable by compressed air which may be controlled by a solenoidvalve. Auxiliary yarn feed means may be provided and comprise an airduct communicating with the yarn entry passage and in the junctionregion therebetween, a venturi formation will be provided to encourageyarn to move into the cutter shaft passage. Where a plurality of feedmeans are required, a plurality of flat plate-like sections may beprovided, each having the channel and openings formed on one surface andbeing built up in side by side juxtaposition to form a unit. A singlewheel may be provided, possibly having a rubber or other coating, andhave a plurality of circular flanges or projections which separate thesections.

Alternatively, the cutting device may include yarn feed means which mayeach comprise a reciprocable yam-pushing member through which yarn maypass and having a portion thereof extending within the yarn entrypassage, a yarn clamp operable to clamp the yarn after leaving thepushing member, and a non-return device adapted to act on yarn withinthe pushing member to ensure yarn passes only towards the cutter shaft.The yarn clamp is arranged to act upon the yarn only during movement ofthe pushing member away from the cutter shaft and only when supply of atuft is required to be produced by the cutting device during thesubsequent movement of the pushing member and non-return device towardsthe cutter shaft.

The cutting device will normally be incorporated in a tufting machinesubstantially as hereinbefore described and arranged to operate insynchronism with the operational movements of the needle bar and othercomponents of the machine such that a tuft of predetermined length willbe provided when desired. One or more cutting devices may beadvantageously provided and supplied with differently coloured yarns.Particular feed means thereof supply a required colour and are operatedto supply tufts of said required colour to the needles of the machineunder control of a colour pattern. In addition to, or alternatively to,tufts of different lengths may be required to form a carpet withsculptured pattern and this may be effected by controlling operation ofthe cutting devices with a suitable pattern. The tuft lengths may bevaried by adjustably controlling the throw of the feed means of acutting device or by actuating cutting devices with different settingsof the feed means. Each needle of the machine may be associated with aplurality of ducting passages of one or more cutting devices althoughsuch are driven so that the needle receives only one tuft peroperational stroke.

A linkage between the feed means and cutter shaft will normally beprovided and have a lost motion action such that the cutter shaft isstationary during part of the revolution or oscillation of the cuttershaft with its diametral passage lined up with the yarn entry passage inthe body. During this time, if required, a predetermined length of yarnis fed by the yarn feed means into the passage in the cutter shaft. Inthe preferred embodiment the linkage subsequently rotates the cuttershaft through substantially 22 or 90, cutting off the yarn fed into itfrom the yarn still left in the body. At the end of the travel, thecutter shaft ceases to rotate and its passage lines up at both ends withthe air passage connected to a pressurized air supply and with the yarnducting passage communicating with the associated needle. When thecutter shaft reaches this position, pressurized air blows the tuft ofyarn from the passage in the cutter shaft to the needle. Thereafter thecutter shaft rotates on 90 or backwards 22 so that its diametral passagelines up once more with the passage in the body, ready for theintroduction and cutting-off of a further tuft of yarn.

With a plurality of cutting devices, all the cutter shafts rotatethrough their predetermined angles at the same time, so that at any onetime, any tuft of yarn fed forward by the feed means operated by thepattern is cut off by a particular cutter shaft, there being only onetuft cut-off at any particular time for one needle. Since all the cuttershaft diametral passages line up with the air passages and the ductingpassages at the same instant, whichever cutter has cut-off a tuft alignsits diametral passage containing this tuft with the air supply, whichthen proceeds to drive the tuft out of the shaft and through all theducting passages and pipes in series into the associated needle.

Since a plurality of needles are required in order to manufacture acarpet, a plurality of cutting device body assemblies will be providedin a tufting machine extending parallel to or at any angle up to 90 tothe needle bar, each body being supplied with yarn. The feed meansassociated with the said bodies may all be driven by a common drive andthe associated cutter shafts may be operated from this power driveeither by means of a linkage, suitably shaped cams or other similarmeans.

The invention will be described further, by way of example, withreference to the accompanying drawings, in which:

FIG. 1 illustrates a cutting device with yarn feed means and cuttershaft; and

FIG. 2 illustrates an alternative embodiment of a cutting device.

The cutting device illustrated in FIG. 1, comprises a composite body 11made up of interconnected sections and having a portion 1 1 defining acurved cutter shaft contacting surface of radius substantiallycorresponding to that of the shaft. A plurality of radially bored yarnentry passages 12 and radially bored air passages 13 are provided inline in the body although only one of each is shown.

A cutter shaft 14 in the form of a cylindrical bar has a plurality oftuft displacing ducts 15 diametrically bored therethrough (only one ductbeing shown in the sectional view). It is to be understood that whilstthe following description refers to component features in the singular,a plurality of such component features are provided in line formation inthe body and cutter shaft and other common components.

Ducting means 16 is provided in a body section 11 and, in use, isconnected via branch pipes (not shown) with the main feed duct (notshown) of a needle of a tufting machine.

Yarn 17 from a creel (not shown) is fed to the cutter shaft 14 by feedmeans which include a clamp comprising an upwardly spring biassed pistonand rod 18 downwardly displaceable in body section 11" by means ofcompressed air entering through duct 19 from a source (not shown) so asto clamp the yarn 17 in passage 12 with the end 18 of piston rod 18.

The yarn feed means also includes a yarn tube 20 securely mounted in areciprocating bar 21 (which in fact carries a plurality of tubes, onlyone of which is shown). One end of tube 20 extends, slidably into theyarn entry passage 12. The other end of tube 20 carries a nonreturndevice in the form of a pawl 22 pivotally mounted on plate 22' securedto the tube 20. The pawl 22 is downwardly biassed to prevent yarn frommoving away from the cutter shaft and to permit movement towards saidshaft. The biassing means comprises a compression spring 23 locatedaround tube 20 and acting between bar 21 and against a flanged slidingsleeve 24 in turn acting on front face of pawl 22.

In operation, yarn 17 extends from a creel (not shown) under pawl 22,through tube 20 and into passage 12 under clamping piston rod 18'. Yarnis caused to reciprocate under clamp rod 18' under the action of thereciprocating bar 21 which is driven by a suitable cam or other means,e.g., Geneva motion (not shown), acting on the bar or an end sectionthereof. Yarn is fed into cutter shaft passage 15 when compressed air iscaused, by suitable control means, to be fed into passage 19 to actuateclamping piston 18 so that yarn is clamped in passage 12 during movementof bar 21 and tube 20 away from the cutter shaft. The action of thenon-return pawl 22 causes the tube to take-in fresh yarn and to pushyarn into aligned passage 15 during its next forward movement; theclamping piston-rod 18 being previously lifted off the yarn. The cuttershaft 14 subsequently rotates through 22 and in so doing the adjacentedges of passages 12 and 15 act to cut the yarn. Passage 15 is thenbrought into alignment with air passage 13 whereupon, under the actionof a slide valve, compressed air blows the tuft 25 out of passage 15,through ducting passage 16 to a feed line of a needle of a tuftingmachine (not shown). The cutter shaft 14 then rotates backwardly through22% into alignment with passage 12 to permit feed of a fresh tuft lengthand the movement is subsequently repeated. Suitable dwell periods in themotion of the cutter shaft will be provided by the drive therefore topermit entry of yarn and exit of tufts to and from the passage 15.

The bar 21 and tube 20 are constantly oscillated in appropriate phasewith the cutter shaft 14, and when no yarn is supplied to the cuttershaft, the tube and its yarn contained therein both oscillatecontinuously. At the most forward position of the tube 20, Le, the onewhere it approaches the cutter, the free end of the oscillating yarnjust reaches the cutting faces between the rotary cutter shaft 14 andthe stationary body portion but does not enter the cutter shaft.

The cutter shafts and tubes oscillate together, the operation of oneclamp causing a tuft to be fed to a particular needle at any particulartime. Since, in a tufting machine, a plurality of needles is required inorder to produce a tufted carpet, a plurality of devices are alsorequired in a tufting machine. The yarn tubes and cutter shafts areoscillated in synchronism by means of for example, eccentrics, cams,levers or chain mechanisms (not shown).

The body portions 1 1 contacting shaft 14 have liners of carbon-metal orother self lubricating metal and the cutting edges of at least passages12 and may have hardened or silver steel bushes (not shown) setthereinto to maintain sharp cutting edges.

The cutting device shown in FIG. 2 differs in that the interconnectedbody sections 11 which receive cutter shaft 14 have air passages 13 andducting means 16 which are arranged to be incorporated in the main feedline of a needle in a tufting machine. The cutter shaft 14 oscillatesthrough 90 and operates in a manner similar to the previous embodiment.The lining metal and bushes previously described are not shown. Similarparts of this embodiment have the same reference numerals appliedthereto.

The non-return device of this embodiment differs substantially from theprevious one and comprise a tube bar 27 having a recess in which a pawl28 is pivotally mounted, extends through an aperture in the tube and isbiassed into engagement with yarn 17 by means of compression spring 29.The bar 27 is mounted on slides illustrated at 30 and is oscillated inphase with cutter shaft by suitable drive means and operates in similarfashion to the previous embodiment.

In this embodiment, ducting means 16 are provided, unlike in theprevious system, which do not individually lead to the main feed line ofa tufting machine, but rather are directly located in the main feed lineand the cutting devices may be arranged vertically, one above the other.

We claim:

1. A cutting device for cutting-off tufts of yarn from a yarn supplycomprising:

a. a body having a portion defining a cutter shaft contacting surface,said body having at least one yarn entry passage and at least one airpassage therethrough each communicating with said cutter shaftcontacting surface,

b. a cutter shaft slidably displaceable with respect to said cuttershaft contacting surface and having at least one tuft displacing passageextending therethrough, said tuft displacing passage being displaceablefrom alignment with said yarn entry passage to alignment with said airpassage, the relative motion of the peripheral edges of the ends of saidtuft displacing passage and said yarn entry passage acting to sever theyarn extending therethrough, c. ducting means disposed with respect tosaid tuft qisfiasimnasasstq c ve tufts therefrom when b. said cuttershaft is a cylindrical bar having said yarn displacing passage extendingdiametrically therethrough.

3. A cutting device according to claim 1 wherein said yarn feed meansincludes:

a. a bar reciprocally displaceable with respect to said cutter shaft,said bar securedly connected to at least one hollow tubular memberextending into said yarn entry passage,

b. means to prevent displacement of yarn within each of said hollowtubular members away from said cutter shaft, and

c. clamping means to prevent displacement of yarn during movement ofsaid hollow tubular member away from said cutter shaft while permittingdisplacement of yarn during movement of said hollow tubular membertoward said cutter shaft.

4. A cutting device according to claim 3 wherein said clamping meansincludes a piston and rod attached thereto, said piston and rod beingreciprocally moveable within a cylinder in said body, said rod extendinginto said yarn entry passage and engaging the yarn therein to preventmovement of said yarn when said piston is acted on by fluid means, saidrod being normally biased away from engagement with said yarn.

5. A cutting device according to claim 3 wherein said means to preventdisplacement of yarn away from said cutter shaft includes a pawlextending into said hollow tubular member, one end of said pawl beingbiased into engagement with the yarn in said hollow tubular mem her toprevent movement of said yarn away from said cutter shaft.

6. A cutting device according to claim 5, wherein said means to preventdisplacement of yarn away from said cutter shaft is mounted in thereciprocable bar carrying said tubular member.

7. A cutting device according to claim 5, in which said tubular memberextends on two sides of the reciprocable bar and said means to preventdisplacement of yarn away from said cutter shaft is attached to the endof the tubular member remote from said cutter shaft. l

1. A cutting device for cutting-off tufts of yarn from a yarn supplycomprising: a. a body having a portion defining a cutter shaftcontacting surface, said body having at least one yarn entry passage andat least one air passage therethrough each communicating with saidcutter shaft contacting surface, b. a cutter shaft slidably displaceablewith respect to said cutter shaft contacting surface and having at leastone tuft displacing passage extending therethrough, said tuft displacingpassage being displaceable from alignment with said yarn entry passageto alignment with said air passage, the relative motion of theperipheral edges of the ends of said tuft displacing passage and saidyarn entry passage acting to sever the yarn extending therethrough, c.ducting means disposed with respect to said tuft displacing passage toreceive tufs therefrom when said tuft displacing passage is incommunication with said air passage, and d. yarn feed means adapted tofeed yarn through said yarn entry passage into said tuft displacingpassage when said passages are in alignment.
 2. A cutting deviceaccording to claim 1 wherein: a. said cutter shaft contacting surface isconcave and cylindrical, and said yarn entry passage, air passage, andducting means extend radially from said surface through said body, andb. said cutter shaft is a cylindrical bar having said yarn displacingpassage extending diametrically therethrough.
 3. A cutting deviceaccording to claim 1 wherein said yarn feed means includes: a. a barreciprocally displaceable with respect to said cutter shaft, said barsecuredly connected to at least one hollow tubular member extending intosaid yarn entry passage, b. means to prevent displacement of yarn withineach of said hollow tubular members away from said cutter shaft, and c.clamping means to prevent displacement of yarn during movemEnt of saidhollow tubular member away from said cutter shaft while permittingdisplacement of yarn during movement of said hollow tubular membertoward said cutter shaft.
 4. A cutting device according to claim 3wherein said clamping means includes a piston and rod attached thereto,said piston and rod being reciprocally moveable within a cylinder insaid body, said rod extending into said yarn entry passage and engagingthe yarn therein to prevent movement of said yarn when said piston isacted on by fluid means, said rod being normally biased away fromengagement with said yarn.
 5. A cutting device according to claim 3wherein said means to prevent displacement of yarn away from said cuttershaft includes a pawl extending into said hollow tubular member, one endof said pawl being biased into engagement with the yarn in said hollowtubular member to prevent movement of said yarn away from said cuttershaft.
 6. A cutting device according to claim 5, wherein said means toprevent displacement of yarn away from said cutter shaft is mounted inthe reciprocable bar carrying said tubular member.
 7. A cutting deviceaccording to claim 5, in which said tubular member extends on two sidesof the reciprocable bar and said means to prevent displacement of yarnaway from said cutter shaft is attached to the end of the tubular memberremote from said cutter shaft.